package jdbc;


import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;

public class JDBCDemo6 {
    public static void main(String[] args) {

        try (
                Connection connection = DBUtil.getConnection();
                ){
            Statement statement = connection.createStatement();
            String sql ="SELECT COUNT(*) count " +
                    "FROM class c " +
                    "JOIN student s ON c.id=s.class_id " +
                    "WHERE c.name='1年级1班' ";
            ResultSet rs = statement.executeQuery(sql);
            while (rs.next()) {
                int count = rs.getInt("count");
                System.out.println("人数"+count);
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}
